BuddyPress.org

What is the differences between BP network activated and BP_ENABLE_MULTIBLOG ?
if BP_ENABLE_MULTIBLOG define as true, is it same with BP network activated ?

i consider it solved after read this https://buddypress.org/support/topic/multi-site-multi-network-questions/

this thread answer my question.
The user can login to any network using username and the password using theirs at main blog.
But, the avatar like mercime said. its only per site. User HAVE TO upload avatar again on each network.